1. Technical Field
The present invention relates to an improvement of a closure for a vial container.
2. Prior Art
Conventional vial containers generally have the following construction. As shown in FIG. 16, a breaking portion 3 encompassed by easily breakable lines 2, such as scores, is formed on the upper surface of a protector 1 made of an aluminum material, an engagement protrusion 5 formed on the inner surface of a synthetic resin cover (hereinafter referred to as a flip-off cap) 4 is fixed to this breaking portion 3 by an eyelet structure, a rubber stopper 6 having a vent slot 7 therein is fitted to a stopper portion 6a inside the protector 1, a drug inside a vial bottle 8 is freeze-dried in such a posture that the rubber stopper 6 is fitted to a bottle mouth 8a of the vial bottle 8 in a lift state, the rubber stopper 6 is fitted completely and air-tightly after freeze-drying, and the skirt portion of the protector 1 is thereafter wound and fastened by a winding machine. This vial container is used in the following way. As shown in FIG. 16, the breaking portion 3 is broken through the flip-off cap 4, the exposed upper portion of the rubber plug 6 is sterilized, a liquid such as distilled water is injected into the vial bottle 8 by piercing a needle such as a syringe so as to dissolve the freeze-dried drug, and the chemical solution is collected into the syringe for injection.
Conventional vial containers are known to have the following problems.
(a) The vial container is made of four kinds of materials, glass, aluminum, synthetic resin and rubber material which must be separated at the time of disposal requiring a great deal of time and labor.
(b) During the process in which the aluminum protector is allowed to stay inside a hopper and then put on a vial bottle through a feeder, aluminum dust is produced which might contaminate the flip-off cap.
(c) The rubber stopper can be lifted off during the transfer to the freeze-drying apparatus.
(d) Since the mouth portion of the vial bottle corresponding to the winding/fastening portion of the aluminum protector is opaque, inspection of the bottle mouth portion is difficult.
(e) When the cover is removed and the breaking portion is exposed, a torn portion of aluminum is formed around the breaking portion which can catch sanitary cotton used for sterilization, and hinder the sterilization of the exposed portion of the upper surface of the rubber stopper.
In an attempt to solve these problems, the applicant of the present invention had previously proposed the vial container shown in Japanese Patent Laid-Open No. 165252/1995. This vial container has the construction shown in FIG. 17. A synthetic resin protector 11 has an opening or a needle piercing window portion 12 closed by seal means 13 which can be easily pierced by a needle, on the top wall thereof, and vent means 17 communicating with the inside of a bottle container 20, inside a cylinder portion 11a thereof. A stopper 15 for sealing the gap between the inner surface of the top wall and the upper surface of a bottle mouth 20a is fitted into the protector 11. Engaging means 18 is disposed on the inner surface of the cylinder portion 11a to keep the protector 11 in a semi-stopping freeze-drying posture before freeze-drying and in a full-stopping seal posture after freeze-drying.